Abstract:Objective: To promote the nasal absorption of recombinant hirudin-2, the preparation and physicochemical properties of recombinant hirudin-2 liposomes, as well as its pharmacokinetic characteristics and bioavailability in rats after nasal administration were investigated. Method: Recombinant hirudin-2 liposomes were prepared by reversal phase evaporation; the test of physicochemical properties including encapsulation efficiency, particle size and stability of liposome suspensions were determined by HPLC; Recombinant hirudin-2 concentration in plasma was determined by chromogenic substrate method and the relative bioavailability and pharmacokinetic parameters were also calculated using software program 3p87. Result: The encapsulation efficiency of recombinant hirudin-2 liposome reached greater than 76.95%,with an average particle size of about 168.3 nm, size distribution ranging from 24 to 286 nm, relative peak width of ±0.47, and a good stability. Conclusion: Compared with recombinant hirudin-2 solution, liposome preparation enhanced the nasal absorption of recombinant hirudin-2.